scholarly journals Universal relation with regime transition for sediment transport in fine-grained rivers

2019 ◽  
Vol 117 (1) ◽  
pp. 171-176 ◽  
Author(s):  
Hongbo Ma ◽  
Jeffrey A. Nittrouer ◽  
Baosheng Wu ◽  
Michael P. Lamb ◽  
Yuanfeng Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Sediment Load ◽  
Yellow River ◽  
Fine Sand ◽  
Sediment Flux ◽  
Universal Relation ◽  
Sediment Grain Size ◽  
Fine Grained ◽  
Predictive Algorithm ◽  
Sediment Size

Fine-grained sediment (grain size under 2,000 μm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 μm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode between mixed suspended bed load transport and suspension-dominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities.

scholarly journals Centennial Impacts of the East Asian Summer Monsoon on Holocene Deltaic Evolution of the Huanghe River, China

2021 ◽  
Vol 11 (6) ◽  
pp. 2799
Author(s):  
Yanping Chen ◽  
Wenzhe Lyu ◽  
Tengfei Fu ◽  
Yan Li ◽  
Liang Yi
Keyword(s):  
Grain Size ◽  
Yellow River ◽  
Asian Summer Monsoon ◽  
River Delta ◽  
Grain Size Analysis ◽  
Size Analysis ◽  
Sediment Grain Size ◽  
Huanghe River ◽  
Huanghe River Delta ◽  
The Huanghe River

The Huanghe River (Yellow River) is the most sediment laden river system in the world, and many efforts have been conducted to understand modern deltaic evolution in response to anthropological impacts. However, the natural background and its linkage to climatic changes are less documented in previous studies. In this work, we studied the sediments of core YDZ–3 and marine surface samples by grain-size analysis to retrieve Holocene dynamics of the Huanghe River delta in detail. The main findings are as follows: The mean value of sediment grain size of the studied core is 5.5 ± 0.9 Φ, and silt and sand contents are 5.2 ± 2.3% and 8.2 ± 5.3%, respectively, while the variance of clay particles is relatively large with an average value of 86.4 ± 8.5%. All grain-size data can be mathematically partitioned by a Weibull-based function formula, and three subgroups were identified with modal sizes of 61.1 ± 28.9 μm, 30.0 ± 23.9 μm, and 2.8 ± 1.6 μm, respectively. There are eight intervals with abrupt changes in modal size of core YDZ–3, which can be correlated to paleo-superlobe migration of the Huanghe River in the Holocene. Based on these observations, the presence of seven superlobes in the history are confirmed for the first time and their ages are well constrained in this study, including Paleo-Superlobes Lijin (6400–5280 yr BP), Huanghua (4480–4190 yr BP), Jugezhuang (3880–3660 yr BP), Shajinzi (3070–2870 yr BP), Nigu (2780–2360 yr BP), Qikou (2140–2000 yr BP), and Kenli (1940–1780 and 1700–1650 yr BP). By tuning geomorphological events to a sedimentary proxy derived from core YDZ–3 and comparing to various paleoenvironmental changes, we proposed that winter climate dominated Holocene shifts of the Huanghe River delta on millennial timescales, while summer monsoons controlled deltaic evolution on centennial timescales.

scholarly journals Impact of change in erosion rate and landscape steepness on hillslope and fluvial sediments grain size in the Feather River Basin (Sierra Nevada, California)

2014 ◽  
Vol 2 (2) ◽  
pp. 1047-1092 ◽  
Author(s):  
M. Attal ◽  
S. M. Mudd ◽  
M. D. Hurst ◽  
B. Weinman ◽  
K. Yoo ◽  
...  
Keyword(s):  
Grain Size ◽  
River Basin ◽  
Sierra Nevada ◽  
Sediment Flux ◽  
Fluvial Sediments ◽  
Sediment Grain Size ◽  
Erosion Rates ◽  
Wide Range ◽  
Feather River ◽  
Order Of Magnitude

Abstract. The characteristics of the sediment transported by rivers (e.g., sediment flux, grain size distribution – GSD –) dictate whether rivers aggrade or erode their substrate. They also condition the architecture and properties of sedimentary successions in basins. In this study, we investigate the relationship between landscape steepness and the grain size of hillslope and fluvial sediments. The study area is located within the Feather River Basin in Northern California, and studied basins are underlain exclusively by tonalite lithology. Erosion rates in the study area vary over an order of magnitude, from > 250 mm ka−1 in the Feather River canyon to < 15 mm ka−1 on an adjacent low relief plateau. We find that the coarseness of hillslope sediment increases with increasing hillslope steepness and erosion rates. We hypothesize that, in our soil samples, the measured ten-fold increase in D50 and doubling of the amount of fragments larger than 1 mm when slope increases from 0.38 to 0.83 m m−1 is due to a decrease in the residence time of rock fragments, causing particles to be exposed for shorter periods of time to processes that can reduce grain size. For slopes in excess of 0.7 m m−1, landslides and scree cones supply much coarser sediment to rivers, with D50 and D84 more than one order of magnitude larger than in soils. In the tributary basins of the Feather River, a prominent break in slope developed in response to the rapid incision of the Feather River. Downstream of the break in slope, fluvial sediment grain size increases, due to an increase in flow competence (mostly driven by channel steepening) but also by a change in sediment source and in sediment dynamics: on the plateau upstream of the break in slope, rivers transport easily mobilised fine-grained sediment derived exclusively from soils. Downstream of the break in slope, mass wasting processes supply a wide range of grain sizes that rivers entrain selectively, depending on the competence of their flow. Our results also suggest that in this study site, hillslopes respond rapidly to an increase in the rate of base-level lowering compared to rivers.

scholarly journals Sediment Grain-Size Characteristics and its Sources of Ten Wind-Water Coupled Erosion Tributaries (the Ten Kongduis) in the Upper Yellow River

Water ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 115 ◽  
Author(s):  
Hui Yang ◽  
Changxing Shi
Keyword(s):  
Grain Size ◽  
Yellow River ◽  
The Yellow River ◽  
Alluvial Fans ◽  
Dune Sand ◽  
Natural Sediment ◽  
Sediment Grain Size ◽  
Sediment Erosion ◽  
Sediment Profiles ◽  
Upper Yellow River

Understanding the composition and sources of deposited sediments in watersheds has great significance on exploring the processes of sediment erosion and deposition, and controlling soil losses in rivers. In this paper, we investigate the grain-size composition parameters and their reflections on sediment erosion, transport and deposition processes in the Ten Kongduis, which are large arroyos carrying a large volume of coarse sediment into the upper Yellow River. The sediments delivered by the Ten Kongduis come from three kinds of sources, including the clasolite (mudstone, sandstone and conglomerate) and loess in the upstream reaches and the aeolian sand in the middle stream reaches. A portion of the sediments is carried to the Yellow River and another portion is deposited in the alluvial fans in the lower reaches of the kongduis. We found two types of deposits in the drilling cores on the alluvial fans and in the sediment profiles, i.e., the sediments deposited by hyperconcentrated flows and those by non-hyperconcentrated or ordinary sediment-laden flows. The deposits of hyperconcentrated flows were only found in some natural sediment profiles exposed on the riverbank slopes. They have a mean size in a narrow range of 0.016-0.063 mm but are very or extremely poorly sorted according to nine samples collected from four kongduis. Most of the sediments carried by the non-hyperconcentrated flows have a mean grain size in the range of 0.05–0.25 mm. We calculated the contributions of sediment from the sources using the grain-size fingerprint method based on grain-size data of the sediment sources and deposits in the alluvial fans for both the hyperconcentrated flows and non-hyperconcentrated flows. It was found that a proportion of 69% or above of sediment carried by the hyperconcentrated flows mainly comes from the clasolite and loess strata in the upper reaches, and 8%–31% from the desert in the middle reaches. The clasolite and loess strata contribute 64%, on average, of the particles above 0.05 mm carried by the hyperconcentrated flows, and the desert in the middle reaches contributes the other 36% or so. The sediments carried by non-hyperconcentrated flows down to the alluvial fans come from the clasolite, loess and dune sand in different proportions in different kongduis with the contributions of both clasolite and dune sand being related roughly to the ratio of upper drainage area to the width of desert in the middle reaches of kongduis. Over 90% of the sediments carried by the non-hyperconcentrated flows into the Yellow River are below 0.05 mm.

Late Holocene Lake Sedimentology and Climate Change in Southern Alberta, Canada

1998 ◽  
Vol 49 (1) ◽  
pp. 96-101 ◽  
Author(s):  
Celina Campbell
Keyword(s):  
Grain Size ◽  
Ice Age ◽  
Low Flow ◽  
Sediment Grain Size ◽  
High Discharge ◽  
Climate Fluctuations ◽  
Fine Grained ◽  
Fine Sediments ◽  
Southern Alberta ◽  
Paleoclimate Proxy

Climatic changes in southern Alberta, Canada, for the past 4000 yr are reflected in a high-resolution record of lake sediment grain size. The proposed mechanism for this response is that outflow discharge removes fine-grained sediments, but increasingly fine sediments are retained and deposited as streamflow declines. At the same time, coarse sediments are brought in by high discharge entering the lake. The net effect of these two processes is to leave coarse, clay-deficient sediments during times of high streamflow and clay-rich sediments during times of low flow. The grain-size record from Pine Lake reflects historic climate fluctuations, as well as prehistoric fluctuations including the Little Ice Age and the Medieval Warm Period. Grain size at this site provides a simple, economical, and nonbiologically mediated paleoclimate proxy.

scholarly journals Annual, seasonal and spatial abundance of the seabob shrimp Xiphopenaeus kroyeri (Decapoda, Penaeidae) off the Southeastern coast of Brazil

2014 ◽  
Vol 86 (3) ◽  
pp. 1337-1346 ◽  
Author(s):  
GISELE S. HECKLER ◽  
MATEUS LOPES ◽  
SABRINA M. SIMÕES ◽  
ROBERTO M. SHIMIZU ◽  
ROGERIO C. DA COSTA
Keyword(s):  
Grain Size ◽  
Temporal Distribution ◽  
Fine Sand ◽  
Spatial And Temporal Distribution ◽  
Sediment Grain Size ◽  
Low Salinity ◽  
Sampling Locations ◽  
Xiphopenaeus Kroyeri ◽  
Reproductive Females ◽  
Estuarine Region

We investigated the influence of environmental factors in spatial and temporal distribution of the seabob shrimp Xiphopenaeus kroyeri in Santos Bay and São Vicente Estuary, state of São Paulo, Brazil. Monthly samples were obtained, from May 2008 through April 2010, from four locations in the estuary and four in the bay. No individual was collected in the estuary and this was attributed to the low salinity means recorded in this environment. We collected 109,153 individuals in the bay and there was no difference in abundance between the two years comprised by the study period. The similarity in spatial distribution can be related to sediment grain size that in all sampling locations showed great amount of very fine sand. The largest amount of reproductive females was obtained in early 2010, when temperature was high, and this could have increased the juvenile recruitment in April 2010. According to our results, the distribution of X. kroyeri in the study area is influenced by temperature, which is related to reproduction, and salinity, limiting the entrance of individuals in the estuarine region.

CARACTERIZAÇÃO DOS ASPECTOS SEDIMENTOLÓGICOS E GRANULOMÉTRICOS ASSOCIADOS À FOZ DO RIO COREAÚ – CE, BRASIL

2019 ◽  
Vol 21 (2) ◽  
pp. 265-278
Author(s):  
Tarcyana Câmara Barroso ◽  
Paulo Roberto Silva Pessoa ◽  
Antônio Rodrigues Ximenes Neto ◽  
Jáder Onofre de Morais
Keyword(s):  
Grain Size ◽  
River Mouth ◽  
Fine Sand ◽  
Fine Grained ◽  
Quartz Sands ◽  
Geomorphological Units ◽  
Marine Influence ◽  
Del Rio ◽  
Atmospheric Systems ◽  
Fine Gravel

A zona costeira é um ambiente dinâmico de transição que apresenta uma interface entre os sistemas continentais, marinhos e atmosféricos. A área de estudo se localiza no município de Camocim-CE na região da foz do rio Coreaú, compreendendo também áreas adjacentes em ambas às margens. O objetivo deste trabalho foi analisar os aspectos deposicionais a partir da granulometria dos sistemas ambientais costeiros, para caracterização sedimentológica das principais unidades geomorfológicas da foz do rio Coreaú. Em campo foram coletadas amostras superficiais de três sistemas litorâneos – Duna; Estirâncio e Estuário. A sedimentação da área estudada é controlada pela influência marinha, com a predominância de areias quartzosas muito fina no subsistema duna e estuário. No estirâncio defronte a falésia costeira na margem esquerda houve predominância de cascalho fino. Já o estirâncio da Ilha do amor apresentou areia grossa e muito fina no estirâncio superior e inferior, respectivamente.Palavras-chave: Rio Coreaú; Sedimentologia; Granulometria. ABSTRACTThe coastal zone is a dynamic transition between the continental, marine, and atmospheric systems. The study area is located in the Coreaú river mouth, Camocim-CE. The aim was to characterize the depositional aspects from the grain size and sedimentology of coastal environmental systems to characterize the main geomorphological units. It was collected superficial samples of three coastal systems - Dune; Foreshore and Estuary. The sedimentation is controlled by the marine influence, with the predominance of very fine-grained quartz sands in the dune and estuary. In the foreshore of the coastal cliff at the left margin there was a predominance of fine gravel, as well as coarse and very fine sand in the upper and lower foreshore, respectively (Ilha do Amor).Keywords: Coreaú River; Sedimentology; Grain Size. RESUMEN La zona costera es un entorno dinámico de transición que presenta una interfaz entre los sistemas continentales, marinos y atmosféricos. La zona de investigación está ubicada en la ciudad de Camocim-CE, en la desembocadura del río Coreaú, y además comprende zonas adyacentes en ambas márgenes. El objetivo de la investigación fue caracterizar los aspectos deposicionales desde la granulometría de los sistemas ambientales costeros presentes en la zona, para caracterización sedimentario de las principales unidades geomorfológicas de la desembocadura del río Coreaú. La continuación se recogieron muestras superficiales de tres sistemas litorales – Duna; estrán y estuario. La sedimentación del área está controlada por la influencia marina, con la predominancia de arenas cuarzo muy fina en el subsistema duna y estuario. En la zona intermareale frente al acantilado costero en la margen izquierda hubo predominancia de arena fina. Ya en la zona intermareale de la Ilha do Amor presentó arena gruesa y muy fina en la estrán superior e inferior, respectivamente.Palabras clave: Río Coreaú; sedimentología; granulometría.

Fiber Concrete for 3-D Additive Technologies

2019 ◽  
Vol 974 ◽  
pp. 367-372 ◽  
Author(s):  
Sergey V. Klyuev ◽  
Andrey V. Shevchenko ◽  
E.S. Shorstova
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Fine Sand ◽  
Coarse Sand ◽  
Additive Technologies ◽  
Fine Aggregate ◽  
Cement Ratio ◽  
Fine Grained ◽  
Fiber Concrete ◽  
Concrete Placement

Fine-grained fiber concrete used in 3D printing is significantly different from conventional heavy concrete, which is determined by the increased consumption of cement, low water-cement ratio and the absence of large aggregates. The largest grain size of fine aggregate is selected taking into account the thickness of the section, the frequency and type of reinforcement, as well as the method of concrete placement. Despite the fact that the tensile strength of concrete on fine sand is more than 1.5 times higher than the strength of concrete on coarse sand, while there is a decrease in compressive strength. Due to the peculiarities of the technology of concrete manufacturing for layering, the use of coarse sands is impractical, and therefore it was decided to use quartz sand with a particle size module of 1.12 as a filler.

scholarly journals Patterns of grain-size temporal variation of sediment transported by overland flow associated with moving storms: interpreting soil flume experiments

2011 ◽  
Vol 11 (9) ◽  
pp. 2605-2615 ◽  
Author(s):  
J. L. M. P. de Lima ◽  
P. A. Dinis ◽  
C. S. Souza ◽  
M. I. P. de Lima ◽  
P. P. Cunha ◽  
...  
Keyword(s):  
Grain Size ◽  
Overland Flow ◽  
Strong Relationship ◽  
Flume Experiments ◽  
Sediment Grain Size ◽  
Sediment Yields ◽  
Sediment Size ◽  
Size Evolution ◽  
Mean Grain Size ◽  
Recession Limb

Abstract. This study describes and interprets the evolution of grain-size distribution of sediment yields generated in an experimental soil flume subjected to downstream and upstream moving rain storms. Results of laboratory experiments show that downstream moving storms cause more soil loss than do upstream moving storms. The pattern of sediment grain-size evolution in time during a runoff event exhibits a clear dependence on the direction of storm movement. A strong relationship between overland flow discharge and mean sediment size is found. Nevertheless, the mean grain-size of sediments transported during the rising limb of the hydrograph is coarser than during the recession limb of the hydrograph. This is more marked for downstream moving storms.

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